Source-receptor study of volatile organic compounds and particulate matter in the Kanawha Valley, WV—II. Analysis of factors contributing to VOC and particle exposures

Abstract

The Kanawha Valley region of West Virginia includes a deep river valley with a large population living in close proximity to many potential sources of ambient volatile organic compounds (VOCs). The valley runs approximately 100 km from Alloy to Nitro and is between 100 and 200 m deep. Nearly 250,000 people live in this section of the valley, which includes the state capital of Charleston. Many large chemical manufacturing, transportation, and storage facilities are also located within the valley's walls. The topography, population density, and locations of sources dictate the possibility of high population exposures. To investigate exposures to VOCs emitted by the local industry, simultaneous measurements of 19 VOCs, particle pH, particle elemental composition, inorganic gases, and meteorological parameters were collected over an entire year. With the use of a mobile van, sampling was performed in the valley at three sites. Samples were collected for 15 days per month for 4 months at each site. Both unvariate and multivariate analyses were performed in an effort to resolve source contributions. Results of factor analyses suggest auto-related, transported aerosol, chlorinated organic sources as well as site-specific sources and a single incident source—a forest fire. The techniques employed suggest that inclusion of VOC measurements increase the ability of such studies to identify pollutant sources.